This invention relates to mats for asphalt underlay as a base for asphaltic road surfaces.
In one of its more specific aspects, this invention pertains to a composition mat and binder suitable for use as an underlay for asphalt paving for road surfaces.
The use of non-woven mats as an underlay for asphalt paving is well known. Generally, such mats are employed by first applying to the highway to be repaired an asphalt composition over which the mat is laid and to which the mat adheres. A tack coat may, or may not, be applied over the mat. In either instance, an asphalt mix is then deposited over the mat and the surface is leveled and rolled. One of the mats presently so employed is comprised of non-woven, needle-punched polypropylene.
The most important property such mats must possess is tensile strength. In addition, such mats should possess low porosity to prevent excess asphalt for strike-through, should exhibit high flexibility and elongation and should not cause skin irritation to those handling the mats.